Day-date watch



NOV. 19,70 JEAN-CLAUDE SCHNEIDER v3,537,255

DAY-DATE WATCH Filed Dec. 6, 1968 United States Patent 3,537,255DAY-DATE WATCH Jean-Claude Schneider, Plaisance, Switzerland, assignorto Ch. Tissot 8: Cie, Le Locle, Switzerland Filed Dec. 6, 1968, Ser. No.781,904 Claims priority, application Switzerland, Dec. 22, 1967,18,128/67 Int. Cl. G04b 19/24 US. C]. 58-58 5 Claims ABSTRACT OF THEDISCLOSURE There are known various timepieces which not only give thedate but also the day of the week in two corresponding openings madethrough the dial.

In order to improve the ease of reading and the aesthetic appearance,recent constructions make these indications appear side by side in thesame generally rectangularly shaped window or at least in two juxtaposedwindows separated by a separation which is as narrow as possible.

The indications of the day and the date are carried by dilterentcoplanar members which generally are each equipped with a jump-springdevice ensuring the passage from one indication to the next by an abruptjump in order to avoid the simultaneous though partial appearance of twoindications in the window of the dial. There are known solutions wherethe driving device for the indicating members is a single one whichdrives only one of the members, the driving of the second taking placethrough the first. This solution which, simpler from the point of viewof the driving, becomes more complicated in the design of an adjustmentdevice for the two mobiles since it is necessary to adjust oneindependently of the other. This date setting operation generally takesplace in known manner by giving to the hour hand by means of the settingbutton a reciprocating movement on either side of the point where thedate is changed. To avoid that by this operation the change takes placeon the two members simultaneously which would be contrary to the goalsought the driving of one of the two must take place by means of a pawldevice which makes it move in only one direction.

The obtention of such arrangements is thus fairly complicated and in anyevent causes considerable loss of energy through friction.

The present invention has for its purpose a watch with a day-dateindicating means, these two indications appearing in at least one windowin the dial and which paliates these drawbacks.

This timepiece is characterized by the fact that these two indicationsare carried on two tangential but not coaxial hypocyclic rings, theinner ring driving by its outer teeth the inner teeth of the outer ring,with a single driving mechanism and a single jump mechanism causing thesimultaneous movement and the positioning of the two rings.

The accompanying drawing represents by way of example one embodiment ofthe present invention.

FIG. 1 is a plane view of the device while FIG. 2 is a partial crosssectional view which is perpendicular to the plane of the indicatingmembers.

In these two figures 1 refers to the plate of the movement on which thetwo indicating members slide while bearing on shoulders provided forthis purpose. The member which indicates the days of the week has theshape of a ring 2 which carries indications 21 and includes outer teeth22 and inner teeth 24. Its rotational axis passes through point 23 whichdiffers from the main axis of movement 3-3.

The outer rolling circle of this ring is tangent at point 25 with theinner rolling circle of the ring carrying the date indications.

The same is also a ring 3 whose axis of rotation passes this timethrough point 33 which coincides with the main axis of the movement. Thering 3 carries the date indications at 31 and includes inner teeth 32meshing along a certain distance on either side of point 25 with thecorresponding teeth 22 of ring 2 and thus positioning it relativethereto. Its position in the plane is ensured on the one hand by itstaking support at point 25 and on the other hand by three spring wires41, 42, 43 supporting it relative to plate 1 and bearing tangentiallyagainst the bottom of a groove 34 on its periphery. The two springs 42and 43 make it possible for ring 3 to slide to the right parallel totheir axis if it is subjected to a force exerted against spring 41. Ring3 comprises a second inner toothing 36 carried by ring 35 applied itselfagainst ring 3.

The driving device is constituted by a cam 51 whose rotational axis isat 52, and actuating lever 53 pivoted at 54 and which has a fixed roller55 sliding around the outer periphery of the cam. Lever 53 moves againstthe urging of spring 59 which progressively stores the energy necessaryfor the abrupt movements of the indicating members. Lever 53 itselfactuates a spring lever 56 also pivoted at axis 54 and which has acurved narrowed part 57 terminating into a rounded pusher 58. Thejudicious shape given to cam 51 gives once a day an abrupt movement tolever 53 and to lever 56, the length of this movement corresponding to astep in teeth 24. The return movement takes place slowly during 24 hourswithout a reverse driving of teeth 24 taking place owing to thejudicious shape of the teeth and of spring lever 56.

The jumper device is constituted by a U-shaped spring 61 bearing on theone hand against a fixed washer 62 and on the other hand against aroller 63 whose support between two teeth of teeth 24 retains in placering 2.

Once every 24 hours the driving device thus leads ring 2 to turn of aturn. By meshing teeth 22 on teeth 32 the disc 3 undergoes a movement ofequivalent length. But owing to the difference in diameter of the tworolling circles, this movement corresponds to Vs of a turn of disc 3.When the date changes, disc 3 will thus advance by two divisions, whencethe necessity of inscribing the same not in the simple numerical orderbut in the following order:

1-17-218-319 etc. 14-30-15-31-16 There results from the previouslydescribed construction that disc 2 makes one turn in two weeks, whiledisc 3 makes two turns in a month. It also results that the respectivediameter of their rolling circles must be selected in the ratio of28/31.

To set the date two procedures must be followed:

If it is desired-to change the indication of the day, for example whenthe watch is first started or after it has been stopped for a while,there is resorted to the known method which consists in giving areciprocating movement to the hour hand by means of the button on eitherside of the position which corresponds to midnight. Upon each of thesemovements, ring 2 which indicates the day will advance by one notch. Itwill also drive in its advance the date ring 3 which will have advancedby as many units as the ring indicating the days will have mademovements.

The second procedure is concerned with the adjustment of the ring whichindicates the date alone, during initial adjustment of the watch or whengoing from one month to the other when the elapsed month has less than31 days. The winding stem is then pulled into a third position which hasfor eifeet simultaneously to mesh a pinion fast on the winding sterninto teeth 36 of ring 35 fast on ring 3 and to free teeth 32 from 22 bymoving ring 3 against spring 41. When the desired date appears in thewindow of the dial it sufiices to repush the winding stern back intoplace and ring 3 will resume its normal position under the urging ofspring 41. a

What is claimed is: p 1.;In a day-date indicating timepiece, an innerring and an outer ring carrying said indications, one of said ringscarrying the date indication'and the other of said rings carrying theday' of the week indication, said rings be ing hypocyclically tangentbut non coaxial, the inner ring having outer teeth driving the innerteeth of said outer ring, and a single driving device and a singlejumper mechanism in contact with said rings to simultaneously move themand position them.

2. Timepiece according to claim 1, wherein said rings have a rollingratio of 28/ 31;

3. Device according to claim 1, having springs urging against said outerring in such a way as to free the teeth thereof outside of said'innerring and to adjust it to a desired date independent of said inner ring.

4. Timepiece according to claim 1, wherein said inner ring comprises twoconsecutive series of the seven days of the week and moves by of a turneach day.

5. Timepiece according to claim 1, wherein said outer ring moves by A ofa turn each day and that the dates thereon are inscribed in thefollowing order:

1-17218-319 etc. 143l)153116 References Cited G. H. MILLER, JR.,Assistant Examiner STEPHEN J. TOMSKY, Primary Examiner

